Macronutrients, also referred to as “macros”, are nutrients that your body needs in large amounts. They give us energy and maintain the body’s systems and structures to function properly. A healthy balanced diet consists of all three macronutrients: carbohydrates (carbs), fat and protein. While carbs and fat have often been demonised, the opposite has been true for protein.
Protein is made up of tiny building blocks called amino acids. When we consume protein in food and drinks it is digested and broken down into amino acids. Our body then uses these amino acids to make new proteins such as muscle, tissues, enzymes and hormones.
There are about 20 different types of amino acids that join together in different combinations to make up protein. The body can produce 11 of these amino acids and these are called the “non-essential amino acids”. The other 9 are called the “essential amino acids” and cannot be synthesised naturally by the body. We must obtain these essential amino acids from the foods we eat as they all have unique properties that are needed for our bodies to function normally.
We need to include protein in our diet daily because our bodies can’t store protein the same way they do with fats and carbs. Our muscles are made largely of protein and enable us to do all sorts of activities like running, dancing and even day-to-day tasks like lifting objects. Protein is also necessary for our immune system, digestion, hair and nail growth, and numerous other bodily functions.
Build – protein is an important building block of bones, muscle, cartilage, skin, hair and nails.
Repair – required to build and repair tissue.
Digestion – production of enzymes, which are proteins necessary to digest food and make new cells.
Oxygenation – formation of haemoglobin, which is a protein found in the red blood cells that carry oxygen in your body.
Regulation – protein plays a role in hormone regulation.
Eating adequate amounts of protein is important during weight loss as it plays a role in maintaining, repairing and building muscle. If you are trying to reduce body fat then eating enough protein can help prevent loss of muscle mass. If you are also exercising regularly then eating enough protein can support muscle repair and recovery.
In addition to the functional quality, protein provides in our bodies, it has been shown that increasing your protein intake helps increase feelings of fullness, known as “satiety”, or decrease feelings of hunger. This might help support weight loss and assist with maintaining weight in the long term. Protein also takes longer to digest than carbohydrates, which can assist with feeling satisfied for longer.
While it can help build and renew muscle, protein still provides calories so if you eat too much your body may store the excess as fat. According to the most recent national nutrition survey, 99% of Australians get enough protein through the food they eat. This means protein shakes, powders and supplements are unnecessary for most Australians’ health needs.
Muscle maintenance is particularly important as you get older, with sarcopenia (a loss of muscle mass and function) being a common feature of ageing. The main effect of muscle loss is a reduction in muscle strength which can lead to a reduction in physical function, as well as impaired mobility and balance. Because of this, and because older bodies may be less efficient at using dietary protein, the minimum protein requirements for people aged over 70 years are higher than they are for younger adults. Furthermore, people who prioritise protein intake tend to maintain greater bone mass, which can lower the risk of osteoporosis and fractures as we age.
Protein is found in a wide variety of foods. When looking at the Australian Dietary Guidelines, the two main food groups that contribute to protein are:
Lean meat and poultry, fish, eggs, tofu, nuts and seeds and legumes/beans.
Milk, yoghurt, cheese and/or alternatives (mostly reduced fat)’ food groups.
Lean red meat is high in iron and can be an important food, especially for some groups including infants, children, women (particularly when pregnant) and athletes.
In addition to protein, milk, yoghurt and cheese are rich sources of calcium and other minerals and vitamins, including B12. Consumption of milk, yoghurt and cheese can protect us against heart disease and stroke, can reduce our risk of high blood pressure and some cancers, may reduce our risk of type 2 diabetes and may contribute to stronger bones.
We mentioned essential and non-essential amino acids earlier, and this is an important consideration when looking at food sources of protein. Animal-based sources of protein contain all of the essential amino acids whereas most plant-based sources do not. That’s why people who follow a vegetarian or vegan dietary pattern should consume a wide variety of plant-based proteins to obtain the right combination of essential amino acids.
Everyone has different protein needs depending on factors such as weight, gender, age and overall health. It is recommended that around 15-20% of total energy intake each day is from protein. In general, you should aim for 0.75 – 1.0g / kg body weight each day. For example, if you weigh 80kg that would mean you require 80g of protein each day. Our Lite n' Easy high-protein meal plans provide more than 90g of protein each day. Older adults should aim for 1.2g/kg body weight due to their higher requirements. Lite n' Easy's My Choice Dinners are designed to provide, on average, 30g of protein per serving, to help older Australians meet their protein needs.
As with most things in life, there can be too much of a good thing. Like all macronutrients, protein provides energy, which is measured in Calories. Consuming additional protein above your needs can contribute to excess energy intake and weight gain. Further, a high protein diet that contains lots of red meat and higher amounts of saturated fat might lead to a higher risk of heart disease and colon cancer.
A great tip is to try and eat high-quality sources of lean protein and spread them evenly throughout the day. This means trying to have some protein at breakfast, lunch and dinner as well as including some protein-rich snacks.